Choose the most appropriate phrases given below the sentence to replace the phrase printed in bold letters to make the sentence grammatically correct. Choose the best option among the five given alternatives that reflect the correct use of the phrase in the context of the grammatically correct sentence. If the sentence is correct as it is, mark “No correction” as the answer.

He's walking upto thin ice by lying to his boss about his work.

Correct option is D

The correct phrase to use in this context is option (d) " walking on thin ice". The correct sentence formed will be: " He's walking on thin ice by lying to his boss about his work”. In the sentence, “walking on the ice” is an idiomatic expression that is used to describe a situation where someone is taking a risk or doing something dangerous that could have serious consequences.
The given sentence "He's walking upto thin ice by lying to his boss about his work" contains a preposition error. The correct preposition to use with this idiom is "on" because the expression refers to the act of walking on the surface of thin ice.
Option (a) “ walking in thin ice” contains an article error. The article "in" implies that the person is already immersed or submerged in the thin ice, which is not the intended meaning.
Option (b) “ walking under thin ice” contains a directional error. The preposition "under" implies that the person is below or underneath the thin ice, which is not the intended meaning of the idiom.
Option (c) “ walk on thin ice” contains a verb tense error. The use of "walk" is in the simple present tense, which suggests a general truth or a habitual action, rather than a specific ongoing action that is happening at the moment.